1. Field of the Invention
The present invention relates to a software and hardware infrastructure allowing for the management of any network device regardless of its location utilizing only a single communications protocol.
2. Description of the Prior Art
Although a browser can be used to directly request images, video, sound etc. from a server, more usually, an HTML document converts the presentation of information served to the browser by a server. However, generally the contents of an HTML file are static in that the browser can only present a passive snapshot of the contents at the time the document is served. In order to present dynamic information, such as information generated by an application or device or to obtain from the user data which has been inserted into an HTML-generated form, conventional world wide web service employ a “raw” interface such as a common gateway interface (CGI). The HTML file provides no mechanism for presenting dynamic information generated by an application or device, except through the CGI.
With respect to obtaining data from a user for use by the application or device, although standard HTML provides a set of tags which implements a convenient mechanism for serving interactive forms to the browser, complete with text fields, check boxes and pull down menus, the CGI must be used to process submitted forms. Form processing is important to remote control, management, configuration, monitoring and diagnosing applications because forms processing is a convenient way to configure an application according to a user input utilizing the world wide web communications model. Unfortunately, form processing employing a CGI is extremely complex, requiring an application designer to learn and implement an unfamiliar interface. Therefore, a CGI is not a suitable interface for rapid development and prototyping of graphical user interfaces (GUI).
Furthermore, a developer must then master a native application source code language (such as C and C++), HTML and the CGI, in order to develop a complete application along with its user interface. Additionally, the CGI mechanism assumes access to the application on the customer's site, but not to the object. The person or process that invokes the CGI program must have full knowledge of that program. A firewall is not in control of the CGI. Therefore, the use of the CGI would make it impossible to fully secure communications between users. Finally, the CGI mechanism works only in the client server environment communicating to one server. This method cannot be applied to the distributed multi-process environment, if only a single communications protocol for the entire system is to be utilized.
Other systems could be used instead of the CGI. For example, an object model such as Microsoft's DCOM or the object management groups internet inter-ORB protocol (IIOP) or the common object request broker architecture (CORBA) could be employed. However, these technologies have some limitations when it comes to creating web services. For example, DCOM and IIOP/CORBA are rich environments, which means that implementations and applications that use them tend to be complex and symmetrical. In other words, to build a distributed application using them, one typically must require the same distributed object model running at both ends of the connection. However, the internet does not guarantee the specific kind of client or server software which would be running at the second end of the connection. All that is required is that the connection understands the hypertext transfer protocol (HTTP). Additionally, it is often technically impossible to insure that all applications would run either IIOP or DCOM.
Any server connected to the internet can potentially be accessed by an internet user, which raises some obvious security problems. To address these concerns, most organizations insert a firewall between their publically accessible web servers and the masses that can access the servers. Generally, a firewall can block incoming traffic based on various criteria and thereby increase an organization's confidence in the security of its system. While they are essential to the secure use of the internet, firewalls make the efficient use of distributed object protocols very challenging. Understanding why firewalls cause problems for distributed object protocols requires understanding of how a firewall is able to distinguish one protocol from another. For example, in the TCP/IP architecture, each widely used protocol is assigned its own port number and each request made using this protocol carries that number. HTTP, for example, is generally assigned port 80, while, for example, the file transfer protocol (FTP) relies on port 21. Most firewalls allow blocking a specific protocol by rejecting all traffic sent on the port used by that protocol. In general, firewalls are configured to allow traffic on port 80. If this was not the case, HTTP requests from browsers could not be received. However, many firewalls block most other ports. This would result in other protocols not being received by the user's local server.
Unlike HTTP, FTP and other widely used protocols, distributed object protocols do not generally have a single well known port number assigned to them. Instead, these protocols typically use dynamically assigned ports, with port numbers chosen arbitrarily as needed. If no firewall intervenes in the communication between the client and the server, this approach works fairly well. If a firewall is asserted, communication stops because the firewall blocks all traffic using this protocol since it is not configured to pass requests on arbitrary port numbers.
One response to this challenge is to use existing internet standards such as an HTTP and XML. More than any other application protocol, the HTTP connects most users to one another. Millions of web sites and browsers utilize protocol.
The problem with HTTP alone is that it is mainly a mechanism for passing files from a server to a client. To create more ambitious web servers, the HTTP must be expanded.
One manner of extending the HTTP would be to use an object protocol such as the simple object access protocol (SOAP) copyrighted by IBM, Lotus Development Corporation, Microsoft and User Land Software. This protocol adds a set over the HTTP headers and rich XML payload to enable complex application-to-application communication over the internet. In other words, the SOAP messaging protocol uses HTTP to carry messages that are formatted with XML.